In Chinese medicine, the body is seen to have many different types and uses of and for Qi. (Loosely translated as ‘energy’) Our personal Qi circulates within and around us, and can be seen as being a power source.
We live by virtue of our ability to manufacture more Qi – to allow us to maintain our equilibrium in the face of change (homeostatic balance), and to repair and reproduce ourselves.
When we lack Qi – we may have some or all of the symptoms outlined.
This is not when you feel as though you have no energy –but when you really don’t. Most feel as though this is so – when in fact their Qi is just stuck /congested/ blocked. For comparison – here is lack of Qi – as evidenced when someone is really ill with an illness that has wasted their ability to function.
Living becomes more difficult and we may struggle to survive. You may see yourself here. Many may have been told that their thyroid is ‘fine’, according to blood tests. Qi deficiency shows as a lack of ‘oomph’. May have a very low BBT if it is measured vaginally as a woman.
Qi is divided for ease of understanding usually into concepts of Yin and Yang.
Neither concept exists without the other, Yin is the oil that lubricates the engine, Yang is the spark that ignites the engine
Yin Qi
The more ‘real’ (physical/structural/obvious) as aspect of something is that which is its Yin. It is always relative to its counterpoint, Yang (that which is more vibrational /resonant/spiritual). Anything considered Yin has relatively more density and physicality than Yang. Unlike Yang, it has boundaries we can sense.
In the body, Yin energy is that which allows rest and regeneration. It is that which cools, moistens and nourishes. Healthy Yin Qi lets us renew ourselves through sleeping, recharging ourselves to go again.
When we choose to live hooked on adrenaline, or perpetually rushed and/or in crisis, we may keep going well past what is reasonable, either because study and /or work deadlines or because we feel it is ‘boring’ to shut ourselves away to rest or sleep. In this way, have no doubt you will wear out your body and its reserves sooner than necessary.
If you do not all your body to fully recharge life’s batteries, thus replenishing your Yin, life will indeed be a struggle.
Yang Qi
The 
term Yang loosely fits our understanding of the concept of ‘metabolism’.
Without strong ‘oomph’ we do not have the life force to be here on Earth, to live our lives.
Yang keeps us here, warm and alive.
Yang is our powerhouse.
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